Internet service providers can provide satellite Internet service to users through geostationary satellites which may offer high data throughput. In addition to the high throughput, the coverage area of satellite networks is also very big compared to other wireless networks that may be available in recent times. Satellite networks often provide coverage in many rural areas where other wireless networks may not be available. However, satellite communications have higher latencies compared to other wireless communications due the data having to travel long distances to the geostationary satellite. Although satellite communications provide very high performance for downlink data, performance of communications through satellite may not be satisfactory for uplink data, especially if uplink is done from many devices at once, i.e. from customers of the Internet service providers.
The paper titled “Networking using Direct Broadcast Satellite” (Venkata Padmanabhan, Hari Balakrishnan, Keith Sklower, Elan Amir, and Randy H. Katz. Networking using Direct Broadcast Satellite. In Proc. of the 1st international Workshop on Satellite-based Services, Rye, New-York, November 1996. University of California at Berkeley) presents a networking architecture where a geostationary satellite broadcasts directly to user premises, while outgoing traffic from the user premises to the Internet is sent over an SLIP/PPP line. This paper explains in detail an asymmetric routing technology. There are two options for sending packets from the users to the Internet. In the first option, packets are encapsulated and sent over the SLIP line using DBS source address. In the second option, home agent-based routing is used.
Users may enjoy high downlink bandwidth when accessing the Internet through a satellite network. However, for transmitting packets to a host or node accessible through the internet, using wireless networks other than a satellite network may provide lower latency and may be cost effective. For a data session using a connection-oriented protocol, techniques are required for automatically enabling a user to use a satellite network for downlink and another wireless or wired network for uplink, while taking into account the asymmetric bandwidth and asymmetric latency.